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.TH CURLOPT_SEEKDATA 3 "December 04, 2023" "ibcurl 8.5.0" libcurl

.SH NAME
CURLOPT_SEEKDATA \- pointer passed to the seek callback
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SEEKDATA, void *pointer);
.fi
.SH DESCRIPTION
Data \fIpointer\fP to pass to the seek callback function. If you use the
\fICURLOPT_SEEKFUNCTION(3)\fP option, this is the pointer you get as input.
.SH DEFAULT
If you do not set this, NULL is passed to the callback.
.SH PROTOCOLS
HTTP, FTP, SFTP
.SH EXAMPLE
.nf
#include <unistd.h> /* for lseek() */

struct data {
  int our_fd;
};

static int seek_cb(void *clientp, curl_off_t offset, int origin)
{
  struct data *d = (struct data *)clientp;
  lseek(d->our_fd, offset, origin);
  return CURL_SEEKFUNC_OK;
}

int main(void)
{
  struct data seek_data;
  CURL *curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_SEEKFUNCTION, seek_cb);
    curl_easy_setopt(curl, CURLOPT_SEEKDATA, &seek_data);
  }
}
.fi
.SH AVAILABILITY
Added in 7.18.0
.SH RETURN VALUE
.SH "SEE ALSO"
.BR CURLOPT_DEBUGFUNCTION (3),
.BR CURLOPT_IOCTLFUNCTION (3),
.BR CURLOPT_SEEKFUNCTION (3),
.BR CURLOPT_STDERR (3)
